High-throughput printing of nanostructured semiconductor precursor layer

Abstract

Materials and devices are provided for high-throughput printing of nanostructured semiconductor precursor layer. In one embodiment, a material is provided that comprises of a plurality of microflakes having a material composition containing at least one element from Groups IB, IIIA, and/or VIA. The microflakes may be created by milling precursor particles characterized by a precursor composition that provides sufficient malleability to form a planar shape from a non-planar starting shape when milled, and wherein overall amounts of elements from Groups IB, IIIA and/or VIA contained in the precursor particles combined are at a desired stoichiometric ratio of the elements. It should also be understood that other flakes such as but not limited to nanoflakes may also be used to form the precursor material.

1 . A material comprising: 
 a plurality of microflakes having a material composition containing at least one element from Groups IB, IIIA, and/or VIA;    wherein the microflakes are created by milling precursor particles characterized by a precursor composition that provides sufficient malleability to form a planar shape from a non-planar starting shape when milled, and wherein overall amounts of elements from Groups IB, IIIA and/or VIA contained in the precursor particles combined are at a desired stoichiometric ratio of the elements.    
     
     
         2 . The material of  claim 1  wherein the milling transforms at least 50% of the precursor particles into microflakes.  
     
     
         3 . The material of  claim 1  wherein the milling transforms at least 95% of the precursor particles into microflakes.  
     
     
         4 . The material of  claim 1  wherein the milling transforms substantially all of the precursor particles into microflakes.  
     
     
         5 . The material of  claim 1  wherein precursor particles are 10 microns or larger when measured along their longest dimension.  
     
     
         6 . The material of  claim 1  wherein the milling occurs in an oxygen free atmosphere to create oxygen free microflakes.  
     
     
         7 . The material of  claim 1  wherein the milling occurs in an inert gas environment to create oxygen free microflakes.  
     
     
         8 . The material of  claim 1  wherein the milling occurs at room temperature.  
     
     
         9 . The material of  claim 1  wherein the milling occurs at a cryogenic temperature.  
     
     
         10 . The material of  claim 1  wherein the milling occurs at a milling temperature wherein all elements in the precursor particles are solids and have the precursor particles have a sufficient ductility at the milling temperature to form the planar shape from the non-planar starting shape.  
     
     
         11 . The material of  claim 1  wherein the milling occurs at a temperature less than 15 degrees C.  
     
     
         12 . The material of  claim 1  wherein the milling occurs at a temperature less than −200 degrees C.  
     
     
         13 . The material of  claim 1  wherein the precursor particles are single metal particles.  
     
     
         14 . The material of  claim 1  wherein the precursor particles are elemental particles.  
     
     
         15 . The material of  claim 1  wherein the precursor particles are alloy particles.  
     
     
         16 . The material of  claim 1  wherein the precursor particles are binary alloy particles.  
     
     
         17 . The material of  claim 1  wherein the precursor particles are ternary alloy particles.  
     
     
         18 . The material of  claim 1  wherein the precursor particles are quaternary alloy particles.  
     
     
         19 . The material of  claim 1  wherein the precursor particles are solid solution particles.  
     
     
         20 . The material of  claim 1  wherein the microflakes comprises only Group IIIA materials.  
     
     
         21 . The material of  claim 1  wherein the microflakes comprises only Group IB and Group IIIA materials.  
     
     
         22 . The material of  claim 1  wherein the microflakes comprises only Group IB and Group VIA materials.  
     
     
         23 . The material of  claim 1  wherein the microflakes comprises only Group IIIA and Group VIA materials.  
     
     
         24 . The material of  claim 1  wherein molar ratio of Group IB material to Group IIIA material in the plurality of microflakes is larger than 1.0.  
     
     
         25 . The material of  claim 1  wherein the precursor particles are elemental particles and wherein milling forms alloy microflakes from the elemental particles.  
     
     
         26 . The material of  claim 1  wherein the precursor particles are chalcogenide particles characterized by a stoichiometric ratio of elements that provides the precursor particles with sufficient ductility to form a planar shape from a non-planar starting shape.  
     
     
         27 . The material of  claim 1  wherein the precursor particles are selected from one of the following: copper selenide, indium selenide, or gallium selenide.  
     
     
         28 . The material of  claim 1  wherein stoichiometric ratio of elements varies between microflakes so long as the overall amount in all of the microflakes combined is at the desired stoichiometric ratio.  
     
     
         29 . The material of  claim 1  further comprising size discriminating the microflakes to exclude microflakes above a desired length.  
     
     
         30 . The material of  claim 1  further comprising size discriminating the microflakes to exclude microflakes above a desired thickness.  
     
     
         31 . The material of  claim 1  further comprising size discriminating the microflakes to control size variation of microflakes to a deviation of less than about 30% of the mean length and about 30% in mean thickness.  
     
     
         32 . The material of  claim 1  wherein one standard deviation from a mean length of the microflakes is less than 100 nm.  
     
     
         33 . The material of  claim 1  wherein one standard deviation from a mean length of the microflakes is less than 50 nm.  
     
     
         34 . The material of  claim 1  wherein one standard deviation from a mean thickness of the microflakes is less than 10 nm.  
     
     
         35 . The material of  claim 1  wherein one standard deviation from a mean thickness of the microflakes is less than 5 nm.  
     
     
         36 . The material of  claim 1  wherein substantially each of the microflakes has a thickness about 100 nm or less.  
     
     
         37 . The material of  claim 1  further comprising coating the microflakes with at least one layer of material containing a group VIA element.  
     
     
         38 . The material of  claim 1  further comprising coating the microflakes with at least one layer of material containing selenium and/or a selenide.  
     
     
         39 . The material of  claim 1  wherein the microflakes form a dry powder.  
     
     
         40 . The material of  claim 1  wherein the microflakes have an aspect ratio of at least about 10 or more.  
     
     
         41 . The material of  claim 1  wherein the microflakes have an aspect ratio of at least about 15 or more.  
     
     
         42 . The material of 1 wherein the microflakes contain sodium.  
     
     
         43 . The material of  claim 1  wherein the microflakes contains at least one of the following materials: Cu—Na, In—Na, Ga—Na, Cu—In—Na, Cu—Ga—Na, In—Ga—Na, Na—Se, Cu—Se—Na, In—Se—Na, Ga—Se—Na, Cu—In—Se—Na, Cu—Ga—Se—Na, In—Ga—Se—Na, Cu—In—Ga—Se—Na, Na—S, Cu—S—Na, In—S—Na, Ga—S—Na, Cu—In—S—Na, Cu—Ga—S—Na, In—Ga—S—Na, or Cu—In—Ga—S—Na.  
     
     
         44 . The material of  claim 1  further comprising an ink containing a sodium compound with an organic counter-ion or a sodium compound with an inorganic counter-ion.  
     
     
         45 . A method of using the material of  claim 1  comprising heating the microflakes in a non-oxygen chalcogen atmosphere to form a dense film.  
     
     
         46 . A method of using the material of  claim 1  and further comprising heating the material on a substrate to form a film and then forming a layer of sodium-containing material on the film.